The specific aim of this project is to develop techniques and tools to convert a FORTRAN package from one computer to another and to develop a prototype of such a converter. The immediate application of the conversion techniques and tools is to convert the National Cancer Institute (NCI) Drug Information System (DIS) Software package from the existing 36-bit computer environment (DEC-10 system) to the 32-bit computer environment such as the IBM 370 and DEC/VAX computers. At the end of Phase I, we expect to document all the syntactic and semantic differences between the FORTRAN compilers on IBM 370, VAX, and DEC-10 computers. We will also identify the impacts of the word sizes on the compiler implementations. A prototype of an automatic translator for FORTRAN-77 program will be developed and be used in the conversion of selected DIS programs and files (or other NIH systems). In Phase II, the automatic FORTRAN converter will be further developed and be used in the conversion of all DIS programs and files. We believe that a commercial version of the general automatic FORTRAN converter will be needed by many data processing organizations as well as scientific and research organizations.